3RD GEN TACOMA OVERHEATING

Hello everyone, i know this threads been made before but didnt have to many answers so I'm making this thread in specific to kinda go over my personal experience with over heating on my truck.
Overview: My trucks a 2019 tacoma offroad 4x4 with 16601 miles on it. The overheating started while driving on a trail (weather beyond the hundreds and ac cranked). I first felt the ac blow warm and then slightly lose a little power. Once i noticed it all reminding me of overheating, i then looked over at the gauge and the needle was just a little under the H. I then quickly turned off the truck and let it sit for about 30 minutes then turned it to accessory mode and saw the gauge go back to normal. I then continued through the trail as i was almost out and no longer saw the gauge go back up or ac blow warm. Being that im well within my warranty i then took it to Toyota and had it diagnosed 2 days later (still no issues) and came up with a inconclusive diagnosis. Tech pressure tested engine (as notified by service advisor), checked cooling system, and scanned vehicle to find nothing wrong with vehicle.
As i stated above ive made this thread to share my experience but then also see if anyone else has been in a similar situation as ive seen some people have this happen to them in less rash conditions. I also do understand it was a crazy hot day and cranking the ac and going in a trail wasnt a good idea but just trying to see if anyones had this issue and has had problem return and if so what the corrective action might have been. Any insight would be great. Thanks everyone !

 

Meh idk if it wasn't a "bad" idea. It's a brand new truck, it shouldn't overheat. That being said I've had my truck get hot too. Not quite to H but probably 3/4 hot. If u feel like keeping tabs on it, get an obd2 plug and app to monitor temperature.

 

I’m guessing nothing wrong other than what you were doing. Very hot day, working hard, moving slowly, AC on high? Sounds like a recipe for high engine temps to me.

 

https://www.tacomaworld.com/threads/2018-tacoma-overheating.684420/#post-24133905

 

Kinda got mixed feelings as to the whole hot day working hard thing. I'd like to say that shouldnt happen but then also do see the hard work the trucks doing with the ac cranks so not sure.
I also saw that thread @Tacospike and dont really see anyone saying anything about repairs or visits to the dealer but good i came across it as i also kinda let me know it hasnt happened to just a modded truck.

 

I like the belt driven fans for normal street duty, but I can see an electric being an improvement for slow moving duty.

 

get a bigger rad and electric fans

 

Yes but IMHO a new 2019 taco offroad should not overheat just from being on trails on a hot day.

 

That's my mentality Too. But these trucks do run hot.

 

It shouldnt, but the conditions were probably just right for even a new truck to overheat. That A/C condenser is dumping a crap ton of heat into the engine bay, the truck trans and engine are working the trail, there isnt enough airflow to exchange out all of those things, and the ambient temperature is too high for it to radiate out on its own. I say normal, and you took the correct steps to prevent damage.

 

Wonder if the AC TSB would help/fix this?

 

Idling for how long? I have a 2019 4 cyl and I’ve never seen the temp indicator go over half way (pretty much stays there after warming up) Even idling. How hot was it outside when that happened?

 

You in 4 H or 4 L? I would imagine if you're pushing alot of torque through 4H trying to crawl up something, plus high ambient temps, plus AC on blast dumping more heat, it would result in what happened to you?

 

@davidstacoma Its been multiple times long story once last year when I first got it I was at the border its was roughly 115 and I was in the line 2hours heated up had to put the window down and turn off the ac cuz it blew hot air out we had to rev up the RPMs to cool the engine. (By the way we've been in the line longer and hotter days in past with a corolla 2018 etc.) A older car next to us had their AC blasting. We took it in for service they said they cant fix it cuase they couldn't replicate it. Again Once in the parking lot 30mins its was 105 took ot said they can't replicate the issue and told me its normal for trucks to overheat in idle. It started doing it again since its getting hotter they finally able to replicate the issue they said its a normal function so there not going to add or replace parts, im picking it up this afternoon.

 

@CoTacos hit it on the money. I was in 4 H and slowling crawling through some rocks (not big) but asked for some power and thats kinda where i noticed it. Again Toyota said its coming up clean at the moment so ill just have to keep an eye on it. Also did see people get indicator lights turn on saying vehicle running hot but nothing came up on mine.

 

Aww hell yeah. It's been a while since I've successfully internet diagnosed a car, kinda proud of myself!

 

Ok that makes sense, with it that hot out and idling a long time I can see why the temperature would increase to 3/4. Likely is normal for those conditions. Reving the engine up a little increases the fan speed and helps cool it So you did the right thing there.

 

I often tow and idle mine in the desert and offroad when it’s over 110° with the AC on and it never overheats, my bet is a bad thermostat.

The hot AC is a different issue, there is a current T-SB notice for it that also includes 2020 Models because the condenser doesn’t get enough airflow when the engine is idling. You’ll have to either put your own electric fan in front of the condenser (just simply tie a relay to the AC clutch which will automatically turn on the fan whenever you turn on the air conditioner, or even simpler just put a switch on it),

...or you can let Toyota fix it for you for free according to this TSB:

https://static.nhtsa.gov/odi/tsbs/2019/MC-10166026-9999.pdf

... and let the service guys tear up your dashboard to do it as called for under their dumbf repair procedure for the AC TSB:

https://m.imgur.com/a/0PpKgw7

 

@OnHartung'sRoad thank you I will see if they are willing to do anything when I pick it up this afternoon. It amazes me that it does this since I've never had that happen to me with older vehicles. But also I live in the desert area in Cali sonits always hot....I'm trusting them less and less since earlier this year I've had my whole rear axel replaced drums etc. for a vibration issue in the stearing wheel and it happened again (tookt in for service this friday gor both issues) they said my front rotors were glazed and warped due to excessive heat which they tried to tell me its cause I brake to much. But they resurfaced them and replaced the drums. Sorry thats off topic of the heating issue.

 

You’re welcome. The AC issue TSB covers 2016-2020. As it says in the TSB, in order for them to know for sure, they will have to test it by letting your truck idle in 100° + heat and seeing if the AC doesn’t blow cold. Don’t just take a “no” for it, they have to test it, or at least take your word that it doesn't blow cold when hot out.

I used to have the same issue with the AC, but decided to put my own fans in because I didn’t want them doing their “repair” to my truck.